#include <bits/stdc++.h>
using namespace std;

#define int long long
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

#define int long long
#define MOD 1000000007

vector<int> tree[1000010];

int rtree[1000010]; 

int dfs(int i, int j){
	int ans = (j*(j+1))/2 % MOD;
	for(auto e : tree[i]){
		ans += dfs(e, j+1);
		ans %= MOD;
	}
	return ans;
}

signed main(){
	int n;
	cin >> n;

	int a, b;
	memset(rtree, -1, sizeof(rtree));
	for(int i = 0;i < n-1;i++){
		cin >> a >> b;
		a--; b--;
		tree[a].push_back(b);
		rtree[b] = a;
	}

	int root = 0;
	while(rtree[root] != -1) root = rtree[root];

	cout << dfs(root, 0) << endl;

	return 0;
}